There are known memory cards using a nonvolatile semiconductor memory and USB (Universal Serial Bus) flash drives as data storage media used in electronics devices, such as a personal computer and a digital video camera. The memory cards and USB flash drives are handy because they are small and lightweight, and further, they are excellent in portability. In view of this, various types of electronics devices in which the memory cards and USB flash drives are usable are being developed. For example, image forming apparatuses having a slot for a memory card are commercially available, in these years. In such image forming apparatuses, image data to be printed can be inputted by use of a memory card, and update of firmware and installation of optional software can be performed by use of a memory card.
As such, memory devices, e.g., the memory cards and USB flash drives, are downsized and improved in portability, and can be widely used in various types of apparatus. However, the reduction in size of the memory devices involves a risk of a serious accident that a young child (infant or toddler) accidentally puts a memory device in his or her mouth.
Patent Literature 1 discloses a technique for notifying all around that a memory card is removed, when the removal of the memory card is detected, in order to prevent such accidental indigestion. However, the technique of Patent Literature 1 cannot prevent the accidental indigestion if there is no adult around.
Patent Literatures 2 to 4 disclose techniques for preventing accidental indigestion of a target product, in which techniques a substance that stimulates sense of taste of young children is applied to the target product so that young children do not put it into their mouths by mistake. For example, Patent Literature 2 discloses a semiconductor memory that is covered with a housing having a roughened surface region in which a bittering agent is retained. Further, Patent Literature 3 discloses a small storage medium containing an innocuous emetic substance (denatonium benzoate, epicatechin, humulone). Furthermore, Patent Literature 4 discloses a simulated beverage for toy, containing cyclodextrin.